1. Field of the Invention
This invention relates to methods and apparatus for constructing fill structures such as retaining walls, dams, and the like. More particularly, the invention is directed to a method and apparatus for constructing an exposed face, suitable for use as the visible surface of such structures which may be composed of any of a variety of materials, as, for example, Portland cement concrete, roller compacted concrete, cement treated soil and the like. The face panel system of the invention also acts as a restraining form for the mass as it is being constructed.
2. Description of the Prior Art
Prior art systems for constructing dams and the like are quite costly. One system involves the construction of climbing form walls, which necessitates the time consuming transporting of formwork to and from the job site, and the setting up of the formwork, followed by the stripping of forms after the concrete has set. After this is done, the exposed concrete must be finished, and snapties broken back and patched to produce an acceptably smooth surface. Climbing form walls of this type may not be appropriate, or may be highly inefficient, in use with some cementitious materials.
Another system for constructing a wall for use in a dam or the like is that shown in U.S. Pat. No. 3,686,873 to Vidal. This system, however, is uniquely designed to create stability in a noncementitious fill by the use of heavy and expensive cladding panels and reinforcing straps which must extend a minimum of fourteen feet at the top of a wall and increase considerably in length toward the base of the wall. Such prior art systems necessitate great expense in terms of labor and materials.
Structural stability and safety is also a problem in the prior art, since cladding panels may not be totally secure immediately after placement. Also, provision of a personnel safety barrier introduces extra costs for scaffolding and the like to support workers.